Apparatus for treating granular materials



March-9, 1948. F. G. R. MAGNUSSON ETAL 2,437,395

APPARATUS FOR TREATING GRANULAR MATERIALS Filed July 23, 1943 4Sheets-Sheet 1 I6 Inventors J7 Gwyn M68012,

March 9, 1948. F. G. R. MAGNUSSON ETAL 2,437,395

APPAR ATUS FOR TRE ATING G RANULAR MATERIALS Filed July 23, 1945 4Sheets-Sheet 2 INVENTQR E ER. MAQNU ssou +GMOHom ZLAW M M March 9, 1943-F. G. R. MAGNUSSON EIAL 2,437,395

APPARATUS FOR TREATING GRANULAR- MATERIALS Filed July 23, 1945 4Sheets-Sheet 3 v 6. F01L0li27/ "March 1948- ,F. G. R. MAGNUssoN ETALAPPARATUS FOR TREATING GRANULAR MATERIALS Filed July 25 1943 4Sheets-Sheet 4 zzussozz 1001512 Patented Mar. 9, 1948 APPARATUS FORTREATING GRANULAR MATERIALS Folke Gtista Robert Magnusson, Stockholm,and

' Gustav Valdemar ('jholm, Nockeby, Sweden Application July 23, 1943,Serial No. 495,904 In Sweden June 20, 1942 Claims. (Ci. 34-102) Thisinvention relates to an apparatus for subjecting small materials such asgrain and other granular materials in a drum to a' gaseous medium inorder to dry or moisten the material or actuate it for other purposes.

This invention eliminates certain drawbacks in earlier known processes.In drying of piece goods in rotating drums one has in the known devicesproceeded along two lines. According to one of said methods the dryingmedium passes through perforations or apertures in the shell of the drumand through the layer of the material to be dried in the drum. Accordingto the other method the drying mediumis blown into a Stationary channel;in thematerial to be dried, and during its rotation the drum forcesthematerial to circulate around thechannel, which through apertures in thebottom of the channel lets out the drying medium into the material to bedried. The first mentioned method involves the drawback that packingsmust be provided around the pressure chamber for the drying mediumbecause said medium is to be admitted into the cylindrical portion ofthe rotating drum from a stationary pressure chamber- .Said packings arecomplicated, and. cause, moreover, always greater or smaller losses ofheat. The other method is, for example, connected with the drawbackthatthe drying medium is to pass through material layers of very varyingthickness, whereby the drying medium is utilized inefiectively.

The invention has for its purpose to remove said drawbacks. It issubstantially characterized by the fact that the material is introducedinto a drum, the shell of which surrounds a lower and an upper turningcentre, and at *one side of the drum is raised to the edge of a shaft,an inclined wall or other fall guiding means along which the materialtime after time sinks more or less slowly to the bottom of the drum, andthat the gaseous medium is blown through the material column or layerthus formed.

The invention is illustrated diagrammatically on the accompanyingdrawings in two embodiments.

In Figs. 1, 2 and 8 one embodiment is shown applied in an apparatus inwhich the drum is carried out as an endless conveyor ,with at least twoturning centres. Fig. 1 is a perspective view, and Figs. 2 and 3 showsubstantially two sections perpendicular to one another on a largerscale.-

Figs. 4 to 6 show a longitudinal section AA of Fig. 1 of the .drum invarious detail constructions.

Fig. 7 shows diagrammatically the invention 2 applied in a drum withstationary shell surrounding a conveyor.

In the embodiment according to Figs. 1 to 3 the shell of the drumconsists of an endless conveyor l0 preferably of gas tight material. Inorder to give an idea of the outer aspect of the conveyor the same isshown in perspective in Fig. 1. At each edge the conveyor is fixed in,or formed with, a conveyor chain l l engaging a chain wheel I2. The twochain wheels, whichmay be located on a common shaft passing from end toend, or each on its individual journal are driven synchronously by a'drive device not shown. Two upright walls 2 extend along the wholelength of the drum at such a distance from one another that a shaft 2ais formed between them and end walls IS. The upper and lower ends ofeach wall 2 are connected with curved walls l4 so that a chamber isobtained on each side of the shaft 211. The walls 2 are shown perforatedin Fig. 1 and in Figs. 2 and 3 provided with spaced members 2b. Theconveyor moves between the stationary end walls 16, which are providedwith inlet and outlet openings for material and treating medium. Saidopenings are visible in Fig. 2, one of them I! being outlet for materialand the other [8 inlet for treating medium. The inlet for the materialis indicated by Ila and the outlet for the treating medium by Illa. Theconveyor is guided around the chambers 3 and 4 by guides 25. Said guidesare by means of stays 26, 21 connected with the frame 28 carrying thebearings for the upper turning point of the conveyor and the stationaryend walls l6 of the drum.

The apparatus works in the following manner: The material which is to besubjected to the treating medium, is introduced through the inlet intothe drum opposite the shaft 2a, is conveyed from the bottom of thedrying shaft, below the walls 2 up to the upper edge of the shaft bymeans of buckets 5 located on the inside of the conveying drum shell, isemptied into the shaft, sinks more or less rapidly to the bottom of theshaft, is caught again by the conveyor, and is raised to the shaft edge,i. e. a small portion falls at each revolution out of the drum throughthe outlet H. The speed, at which the material sinks through the shaft,is dependent upon the capacity of the conveyor 5. The feeding throughthe drum is effected through the action of the inclination of the drum.

The chambers 34 on both sides of the drying shaft are used fordistribution and removal of the treating medium. In the described casethe drying air is distributed from the inlet in the chamber 3, passesthrough the shaft and the material can be subjected to treatment bymediums having different properties in the same apparatus, for examplesimultaneously by superheated vapour in one end portion and by fluegases in the other end portion or by drying air and cooling air.

By providing partitions 8 according to the principle shown in Fig. 6 thetreating medium can be led in zigzag through the material, and thus thegas path can be prolonged, and consequently the actuation of the gasupon the material can be delayed. Another way is to pass the medium fromone end of the drying chamber 3 through the shaft to the other chamber4, from there back to the first chamber, and then to take out the samefrom the drum. By means of several partitions the drying medium can beforced to pass several times to and fro through the drying shaft.

In the embodiment according to Fig. 7 the shell is stationary butsurrounds a conveyor 35 having shovels 36 performing the transport ofthe material from the lower portion of the shaft 211 to its upperportion. The shell 37 forms together with the, end walls .16 a closedchamber. As in the previous embodiment the apparatus is provided withinlet and outlet openings for material to be dried as well as for dryingmedium, and the shaft walls 2 are made with perforations 20.

Having now described our invention, what we claim as new and desire tosecure by Letters Patent is:

1. An apparatus for treating materials comprising two substantiallyvertical, stationary end walls, two substantially horizontal hollowbodies located between and fixed to said end walls and having mutuallyfacing walls spaced from one another to form a vertical. shaft betweenthe hollow bodies, said mutually facing walls having perforations forthe passage of a medium from one hollow body to the other right acrossthe shaft, inlet and outlet pipes for the medium in said end wallscommunicating with the interior of the hollow bodies, guide means abovethe hollow bodies, an endless conveyor arranged between the end wallsand depending from said guide means and extending about the outersurfaces of the hollow bodies, an inlet pipe in one end wall fordirecting rnaterial to be treated on to the lower portion of theconveyor, and an outlet pipe in the other end wall for receiving treatedmaterial falling from the upper portion of the conveyor.

2. An apparatus as claimed in claim 1, in which the conveyor and endwals constitute a substantially fluid tight shell. I

V 3. An apparatus as claimed in claim 1, in which the general contour ofthe apparatus in vertical section is pear-shaped, being narrower at thetop than at the bottom.

4-. An apparatus as claimed in claim 1, provided with means for guidingthe lower portion of the conveyor about the hollow bodies. a

5. An apparatus as claimed in claim 1, provided with a partitionarranged in each hollow body.

FOLKE GGSTA ROBERT MAGNUSSON.

GUSTAV VALDEMAR I-IOLM.

REFERENCES CITED The iollowing references areof recordin the file ofthis patent:

UNITED STATES PATENTS

